Automatic merge from submit-queue (batch tested with PRs 53866, 54852, 55178, 55185, 55130). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

Add extra-args configs for scheduler and controller-manager to kubernetes-master charm

**What this PR does / why we need it**:

This adds `controller-manager-extra-args` and `scheduler-extra-args` config options to the kubernetes-master charm.

These allow operators of Juju-based Kubernetes clusters to pass arbitrary arguments to kube-controller-manager and kube-scheduler as needed.

**Release note**:

```release-note
Add extra-args configs for scheduler and controller-manager to kubernetes-master charm
```